I am both Sherlock and Watson! I literally sat and stared at this image for a few seconds and deduced that the passcode was 0179 although the door was already open due to the green light.<<This is post is hilarious I loved Watson at the end
The thing that most american sherlockians don't realize is, in England "trousers" are "pants", and "pants" are "underwear". John isn't talking about Sherlock's pants he's talking about his underwear. One of my favorite scenes.